I Have Been Experiencing White Spots In My Stool For

I have been experiencing white spots in my stool for over 2 months now. I saw my physician and he tested for parasites and that came back negative. I lost 5 lbs in two weeks without trying then gained it all back. I feel blotted, tired, sometimes random pain in my stomach, and starting to feel a little down. I have developed a caffeine sensitivity as well.